# Henry Shum (University of Waterloo)

Date

Tuesday January 23, 20249:30 am - 10:30 am

Location

Jeffery Hall, Room 319 (Via Zoom)## PDEs & Applications Seminar

**Tuesday, January 23rd, 2024**

**Time:** 9:30 a.m. **Place:** Jeffery Hall, Room 319 (Via Zoom)

**Speaker:** Henry Shum (University of Waterloo)

**Title:** Numerical simulations of microswimmers

**Abstract:** Bacteria are relatively simple microorganisms that have evolved surprisingly effective modes of motility that have allowed them to survive and thrive in almost every environment on Earth, including inside the human body. These and other forms of natural locomotion have inspired designs for artificial motility from aircraft to nanorobots. Focusing on microscale motion in viscous fluids, we consider models for flagellated bacterial motility in which long, passive flagellar filaments are turned by a rotary motor to propel the cell forward like a propeller. We use a combination of boundary element methods and the method of regularized stokeslets to numerically solve the equations of Stokes flow around the swimmer and use a Kirchhoff rod model to describe the elastic dynamics of the flagellum. This model is applied to reveal the consequences of various morphological design parameters for bacteria swimming in free space and near solid boundaries. We also discuss a more general mathematical model for a microswimmer and apply it to describe a synthetic system of active droplets.